"The Know-Nothing party was a U.S. political party that flourished in the 1850s. The Know-Nothing party was an outgrowth of the strong anti-immigrant and especially anti-Roman Catholic sentiment that started to manifest itself during the 1840s. A rising tide of immigrants, primarily Germans in the Midwest and Irish in the East, seemed to pose a threat to the economic and political security of native-born Protestant Americans.
In 1849 the secret Order of the Star-Spangled Banner formed in New York City, and soon after lodges formed in nearly every other major American city.
Members, when asked about their nativist organizations, were supposed to reply that they knew nothing, hence the name. As its membership and importance grew in the 1850s, the group slowly shed its clandestine character and took the official name American Party. As a national political entity, it called for restrictions on immigration, the exclusion of the foreign-born from voting or holding public office in the United States, and for a 21-year residency requirement for citizenship.
By 1852 the Know-Nothing party was achieving phenomenal growth. It did very well that year in state and local elections, and with passage of the Kansas-Nebraska Act in 1854 it won additional adherents from the ranks of conservatives who could support neither the proslavery Democrats nor antislavery Republicans. When Congress assembled on Dec. 3, 1855, 43 representatives were avowed members of the Know-Nothing party.
That, however, was the peak of Know-Nothing power. At the American Party convention in Philadelphia the following year, the party split along sectional lines over the pro-slavery platform pushed through by Southern delegates."
Britannica, Know Nothing Party
"I am not a Know-Nothing. That is certain. How could I be? How can any one who abhors the oppression of negroes, be in favor of degrading classes of white people? Our progress in degeneracy appears to me to be pretty rapid. As a nation, we begin by declaring that 'all men are created equal.' We now practically read it 'all men are created equal, except negroes.'
When the Know-Nothings get control, it will read 'all men are created equal, except negroes, and foreigners, and catholics.' When it comes to this I should prefer emigrating to some country where they make no pretence of loving liberty- to Russia, for instance, where despotism can be taken pure, and without the base alloy of hypocrisy."
Abraham Lincoln, Letter to Joshua Speed, August 24, 1855
The Know Nothing Party enjoyed a localized resurgence in the post Civil War period as the Ku Klux Klan, which held a deep prejudice against Black, Catholic, and Jewish Americans and 'foreigners'. It favored the use of violence and terror. The first Klan was a purely Southern phenomenon that died out around 1870.
The resurgence of the Klan was prompted by D. W. Griffith's glamorized portrayal of the Klan in 1915's Birth of a Nation. The 1920's was its period of greatest and most widespread power. It gradually declined in the Second World War.
"The second Klan grew primarily in response to issues of declining morality as typified by divorce, adultery, defiance of prohibition, and criminal gangs In the news every day. Secondly, it was a response to the growing power of Catholics and American Jews with non-Protestant cultural values. [prejudice against Black Americans and foreigners is always assumed in these movements.]
By the mid 1920s the second Klan had a nationwide reach, with its densest per capita membership in Indiana. The Klan became most prominent in cities with high growth rates between 1910 and 1930, as rural Protestants flocked to jobs in Detroit, and Dayton in the Midwest; and Atlanta, Dallas, Memphis, and Houston in the South. In Michigan, close to half of the state's 80,000 Klansmen lived in Detroit."
The nativist movements are just another nearly forgotten chapter of American history that seem to recur whenever change and turmoil arises.